Hi,
You will be able to process M3T images right away, PIX4Dmapper is camera agnostic.
The only thing is that the thermal will provide a colorful visual representation of the temperature. This applies to currently not supported thermal images. Note that it will not be possible to know the pixel temperature values unless you convert your images.
Please refer to: Pix4Dmapper not converting RJPEG images to tiff from Mavic 3T Enterprise, Zenmuse H20T , H20N and Mavic 2 dual enterprise advanced thermal camera